Dermatome attachment



July29,1947. ,LD EESE 2,424,584

DERMATOME ATTACHMENT Filed Nov. 20, 1945 l 3 Sheets-Sheet l INVVENTOR. 'J-OIJN 111E555;

July 29, 1 947. JDREESE 2,424,584

DERMATOME ATTACHMENT Filed Nov. 20, 1945 4 s Sheets-Shed 2 INVENTOR. J04! J E5555 A'r-roZIJE v.

July29, 1947. J. D. REESE I 2,424,584

DERMATOME ATTACHMENT INVENTOR. Jon-N J). EEESE ATTG/ZA/EY Patented July 29, 1947 UN [TED STATES PATENT OFFICE 2,424,584 DERMATOME ATTACHMENT John 1). Reese, Philadelphia, Pa.

Application November 20, 1945, Serial No. 629,875

19 claims. 1 This invention relates to surgical instruments, more particu1ar1y to dermatomes, and has for an object to improve existing devices of this character.

Most dermatcmes in use today are of the 1 site terminal portions of the shaft, and carry at their other ends a graft-cutting knife adapted for cutting movement parallel to, and at a predetermined distance from, the convex surface, M

It is customary to coat the convex surface with a suitable adhesive, so that, as the drum is pressed against donor area and rocked thereon, the skin adheres to the convex surface and is lifted thereby. At the same time, cutting action of the knife separates the skin frcm the donor area; leaving the graft adhering to the convex surface. The graft is thereafter removed from the drum and sutured or clamped to the injured area to be grafted. g M

In applicants copending application Serial No. 618,523, filed September 25, 1945, there is disclosed an improved dermatome of the ,drum type, wherein the drum is provided with means for securing an adhesive-coated flexible strip to the drum with the intermediate portion ofthe strip overlying the drum convex surface, together with means for drawing the strip taut against said convex surface.

This flexible graft-transfer strip takes the place of the adhesive coating appliedtc the convex surface, the cutting operation leaving the graft adhering to the graft-transfer strip, the graft thereafter being applied to the injured area without removal from the graft-transfer strip, the latter providing excellent means for securing the graft in position and eliminating the necessity of using sutures or clamps. V

There are several thousand of the drum type dermatomes in use in the United States, none of which are provided with mechanism for securing thereto, and tightening thereon, the flexible graft transfer strips, which strips are fully dis closed in applicants cope dine application, Serial No, 583,983, filed March 21, 1945.

Therefore, another ob ect of the present inventicn is toprovide an attachment for dermatomes which will retain a flexible g'raft=transfer on the dermatome and draw the strip taut.

Itis' highly desirable that any such attachment be simple in construction, easily assembled on a dermatome, and capable of attachment to the dermatcme without alteration of the existing structure, such as the drilling or holes, tapping of threaded openings, etc.

Therefore, another object of the invention is to provide an attachment for dermatom'es which may be applied to such dermatome without any accretion of the latter.

Yet another object of the invention is to provide an attachment for dermatome's which may be assembled anti/or applied to a dermatome withoiitthe exercise of unusual mechanical skill.

These and other objects are effected by the invehtion as will be apparent from the following description and claims taken in accordance with the accompanying drawings, forming a part of this application, in which: Fig. 1 isa front elevational view of a dermatome on'which is assembled an attachment embodying the principles (if the present invention;

Fig. 2 is a side elevational view of the structure shown in Fig.1; v

Fig. 3 is a sectional View, taken along the line III-III of Fig. 2, looking in the direction indicated b the arrows;

Fig. e is a sectional view, taken along the line rv==rv of Fig. 2, looking" in the direction indicated byt'he arrows;

Fig. 5 is a sectional view, taken along the line V=V of Fig. 2, looking in the direction indicated by the ircwsi Fig. 6 is a fragmentary side View of a modified arrangement for securing the attachment of Figs.

1 pg 5 to the dermatcme;

Fig {is a sectional view, taken along the line YII of Fig.6, looking in the direction indicated by the arrows;

in Fig. 11, portions thereof being broken away for the sake of clearness;

Fig. 13 is a fragmentary side elevational view of the left-hand end of the structure shown in Fig. 12;

Fig. 14 is an elevational view of the inner end of the bushing shown in Fig. 13;

Fig. is an enlarged transverse sectional view of the clamp for the ends of the graft-transfer strip, as shown in Fig. 11; and

Fig. 16 is a side elevational view of a key suitable for operating the tightening mechanism of Figs. 11, 12 and 13.

Referring now to the drawings more in detail, particularly to Figs. 1 and 2 thereof, there is shown a dermatome which, of itself, forms no part of the present invention, being fully disclosed in applicants copending application Serial No. 623,900, filed October 23, 1945, to which reference may be had for a detailed description thereof. It is believed sufficient to state here that the dermatome lo comprises a spaced pair of parallel, semi-circular side walls I and I2, connected at their semi-circular edges by a curved bottom wall l3 having an outer convex surface l4, normally adapted to be coated with adhesive, for the purpose previously mentioned. The side walls H and |2 are connected at their upper edges by a handle |5 bridging the space therebetween and serving as a bearing for a shaft l6 slidably and rotatably journaled therein.

A pair of parallel posts I! and I8 .are secured on the terminal portions of the shaft I6 and carry at their outer free ends a pair of heads l9, to which is secured a blade-supporting structure, indicatedin its entirety by the reference character 2|. This blade-supporting structure may be drawn towards, and held against, the heads |9 by the finger nuts 22' and their associated structure, with the blade 23 held with its cutting edge in parallel predetermined spaced relation with respect to the convex surface 4, variations in the predetermined spacing of the blade 23 relative to the convex surface I4 may be obtained by insertion of shims 24, of the desired thickness, between the blade-supporting structure 2| and the heads l9 (Figs. 2 and 8). The structure so far described is disclosed in detail in applicant's copending application Serial No. 623,900, filed October 23, 1945.

The attachment for the dermatome just described, and constituting the subject-matter of the present invention, provides means for securing a flexible graft-transfer strip to the dermatome, and comprises a pair of side plates 3| and 32 of the same general shape as thedermatome side walls II and I2, but slightly smaller, and have notches 33, in their upper edges to receive the shaft |6 when the side plates are positioned against the outer surfaces of the side walls I and I2. The side plates are provided with circular'bosses 34, 35 and 36 on their inner'surfaces for close reception in mating circular openings A, B and C, respectively, which are provided in the dermatome side walls H and I2 for use in supporting the dermatome or for other reasons not pertinent to the present invention. It will be apparent that the mating of the bosses in the openings A, B and C will prevent movement of the side plates 3| and 32 in the planes of the latter.

A clamping block 3'! extends between the bosses 33'33 and has terminal portions 38 mounted in the bosses, these terminal portions 38 being of non-circular cross-section to prevent turning of the clamping block. A clamping bar 39 likewise extends between the bosses 3333 in parallel relation to the clamping block 31, the bar 39 .being pivotally mounted on a rod or bolt 4| extending through the bosses and the side plates 3|32. A nut 42 retains the bolt 4| in position and the bolt tlrus serves to prevent separation of the side plates from the dermatome (Fig. 5).

The clamping block 3'! and clamping bar 39 have roughened opposed surfaces adapted to clamp between them one end of a flexible grafttransfer strip (not shown), when the clamping bar is moved to clamping position by means of a handle 43, as described in the previously-mentioned lcopending application Serial No. 618,523, in which the same clamping mechanism is illustrated as built into the dermatome.

Referring now to Fig. 4, a shaft 5| is rotatably mounted in the opposed bosses 3434 in the openings B-'B One terminal portion 52 of the shaft 5| extends through the boss 34 and its side plate 3| and is internally bored, as at 53, for reception of any suitable tool or wrench (not shown) which may engage the pin 54 traversing the bore 53, for rotating the shaft 5|, A slot 55 extends longitudinally of the intermediate portion of the shaft 5|, for reception of the other end of the grafttransfer strip whose one end is held by the clamping mechanism previously described. Thus, the two ends of the graft-transfer strip will be gripped with the intermediate portion of the strip engaging the outer convex surface M of the dermatome.

The projecting terminal portion 52 of the shaft 5| has its outer periphery toothed as at 56, for engagement by a pawl 51pivotally mounted on the side plate 3| by the pin 58, and urged into engagement with the teeth 56 by a spring 59. When theshaft 5| is rotated clockwise, as viewed in FigrZ, to hold and tighten the graft transfer strip, the teeth 56 will slip past the pawl 51, but countenclockwise rotation will be prevented by engagement of the pawl with the teeth, until such times as it is desired to release the strip, when the pawl may be disengaged from the teeth by movement of the pawl handle 60 to the left, as viewed in Fig. 2.

. Inasmuch as it is frequently desirable to further tighten the graft-transfer strip by an amount less than that corresponding to the spacing of the teeth 56, a cam shaft 65 is mounted in the bosses 3535 in such a position that the grafttransfer strip rests thereagainst in passing from the left end of the dermatome, as viewed in Fig. 2, to' the slotted shaft 5|, just described. The cam shaft 65 has a terminal portion 66 extending through the boss 35 and its side plate 3|, this terminal portion being hollow, as at 61, and traversed by a pin 68 for engagement by the same tool or wrench used with the shaft 5|. Similarly, the periphery of the terminal portion 66 is toothed, as at 69, for engagement by the pawl 10, pivotally mounted, at H,- on the side plate 3|, and biased into operative engagement with the teeth 69 by the spring 12. 7

With the series of teeth 69 in the position shown in Fig. 2, the cam shaft 65 will be exerting minimum pressure on the contacting graft-transfer strip. Turning of the cam shaft 65 through 180 will put maximum pressure on the strip to tighten the latter, both ends thereof being already held by the previously-described mechanisms.

The bolt M and nut 42 hold the side plates 3I--32 against the dermatome side wall at one end, and they may be held at the other end by screw threaded into one end of the cam shaft 65, and nut 16 threaded on the terminal portion 66 of shaft 65.

In Figs. 6 and '7 there is illustrated a modified construction of attachment differing from that just described in that the side plates 80 are held against the dermatome side walls by hook portions 8|. In this construction, the bosses may be omitted as well as the screw 15 and nut 16.

In Figs. 9 and 10, there is illustrated a modified construction of dermatome attachmentfor securing a graft-transfer strip to a conventional drumtype dermatome. The dermatome shown in Fig. 10, and indicated in its entirety by the reference character I00, differs in detail from that shown in Figs. 1 and 2, but involves the same basic construction, including a pair of opposed, parallel, semi-cylindrical sidewalls IOI, joined along their semi-cylindrical edges by a curved bottom wall I02 having an outer convex surface I03. A cylindrical handle I04 connects the side walls IOI midway of the length of their upper edges, and provides a bearing for a, shaft I05 mounted therein for rotation and reciprocation therein. A pair of posts I06 are mounted on the shaft terminal portions and have at their outer free ends heads I01 against which a blade-supporting bar I08 clamps a knife blade I09. Spacing of the blade-cutting edge III with respect to the convex surface I03 is varied by the insertion, between the blade and the heads I01, of shims -I I2 of the desired thickness, these shims being similar to the shims 24, illustrated in Fig. 8. The: blade-supporting bar I08 is moved toward and away from the heads I01 by knurled adjustment nuts II3 of the tops of the posts I06, through interconnecting mechanism (not shown). For a detailed disclosure of this dermatome I00, reference may be had to applicants Patent No. 2,366,054.

.The attachment of Figs. 9 and 10 is, in effect, a separable liner I for the dermatome I00, and comprises a pair of semi-circular side walls I2I joined along their semi-cylindrical edges by a curved wall I22. The side walls I2I are provided with semi-cylindrical notches I23 at the centers of their upper edges to fit around the dermatome handle I04 when the liner I20 is inserted within the dermatome. I

Securing mechanism I25 is mounted within the liner, at the right-hand end thereof as viewed in Figs. 9 and 10, and comprises a clamping bar I26 having an upper gripping edge I21 and a lower bearing edge I28. Tightening of the clamping bar by the pair of screws I29, threaded in bosses I30 on the inner surface of the liners curvedwall I22 forces the gripping edge I21 into holding engagement with the terminal portion I32 of the flexible graft-transfer strip I33, whose intermediate portion is positioned against the outer convex surface I03 of the dermatome.

The other terminal portion. I35 of the graft transfer strip is held by a securing mechanism I36, similar to the securing mechanism I25, and comprising the clamping bar I3'1 having a gripping edge I38 and a bearing edge I39, together with a pair of screws I40 for forcing the clamping bar into securing position with the gripping edge I38 holding the graft-transfer strip terminal portion I35.

I The screws I40 are threaded into a supporting bar I4I, pivoted at its lower edge, by pin I42, to the left-hand end of the liner I20. An adjusting screw I43 is threaded through the supporting bar I4I, with its point engaging the curved wall I22 of the lever. The head of the screw I43 is provided with a suitable fingerpiece I44 by which it may be turned to move the supporting bar about its pivot I42. It will be apparent that as the supporting bar MI is moved clockwise, as viewed in Fig. 10, the graft-transfer strip I33 will be tightened and the intermediate portion thereof drawn taut against the convex outer surface I03 of the dermatome.

In Figs. 11 to 16, inclusive, there is shown an attachment for use with a dermatome similar to that of Fig. 10, the parts thereof bearing the same numerals. In this modification, a bushing I50 is rotatably mounted in one of the circular side Wall openings C and has secured thereto, by pin I5I, a shaft I52 whose other end is rotatably mounted in bushing I53, which is prevented from turning by ribs I54 (Fig. 14) which slightly out into and grip the wall of the opening C in which it is mounted.

The shaft I52 is of non-circular cross-section between the bushings I50 and I53, and has mounted thereon a pair of parallel arms I55, at

whose free ends is mounted a bar I56. Inasmuch as the openings in the arms I55 are of a size and shape to closely receive the non-circular portion of the shaft, any rotation of the shaft will be imparted to the arms.

That end of the shaft which is journaled in the bushing I53 is slotted, as at I51, for insertion of the blade I58 of a suitable tool or key I59, or for the fiat blade of a conventional screw-driver (not shown), by which the shaft may be rotated. A toothed ratchet wheel I6I is non-rotatably mounted on the shaft I 52 adjacent the outer face of the bushing I53, and the teeth I62 thereof are adapted to be engaged and held from counterclockwise rotation by the pawl I63, pivotally mounted on the bushing I53.

With this attachment, a lon graft-transfer strip I65 is positioned as shown in Fig, 11, with the terminal portions I66 and I61 thereof held together by suitable clamping means, such as the G-clamp I68 (Fig, 15) The intermediate portion I69 of the graft-transfer strip engages the outer convex surface I03 of the dermatome, and the opposite portion I'II thereof is positioned beneath the rod I56. As the shaft I52 is rotated clockwise, as viewed in Fig. 11, the arms I55 will move the rod I56 downward against th portion I1I of the graft-transfer strip, thereby drawing the intermediate portion I69 thereof taut against the convex outer surface of the dermatome.

While the invention has been shown in several forms, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various other changes and modifications without departing from the spirit thereof,

What is claimed is:

1. An attachment for use with a dermatome of the type comprising a hollow body member having an outer convex surface against which a flexible graft-transfer strip is to be temporarily retained taut; said attachment comprising a subporting structure, first means 'carried by said supporting structure for securing to the latter one end of a flexible graft-transfer strip, second means carried by said supporting structure for securing to the latter the other end of said flexible graft-transfer strip with the intermediate portion of said strip positioned against the dermatome outer ,convex surface, said second means being adjustable relative to said supporting structure to draw said graft-transfer member taut against said dermatome convex surface.

2. An attachment as specified in claim 1, wherein said supporting structure includes a pair of parallel spaced-apart side plates having axiallyaligned openings therein constituting bearings, and said second securing means extends between said side plates and has terminal portions journaled in said bearing openings.

3. For use with a dermatome of the type comprising a hollow body member having a convex outer surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said dermatome convex outer surface; said attachment comprising a supporting structure adapted to be attached to the hollow body member of a dermatome of the type specified, first means carried by said supporting structure and adapted to grip one end of a flexible grafttransfer strip, and second means likewis carried by said supporting structure for securing the other end of said flexible strip with the intermediate portion of said strip against said convex outer surface and for pulling said strip to draw said intermediate portion of said strip taut against said convex outer surface.

4. Structure as specified in claim 3, wherein said second means pulls said strip in predetermined increments, and including cam means carried by said supporting structure for tightening said strip a portion of one of said increments.

5. For use with a dermatome of the type comprising a body member having a pair of spacedapart side walls having pairs of axially-aligned openings therein and joined by a bottom wall having an outer convex surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said outer convex surface; said attachment comprising first means for holding one end of the graft-transfer strip and adapted to be supported in one of said pairs of axiallyaligned openings, and second means for holding the other end of said strip with the intermediate portion of the latter against the convex outer surface and for pulling said strip to draw said intermediate portion thereof taut, said second means being adapted to be supported in another of said pairs of axially-aligned openings.

6. Structure as specified in claim 5, including cam means for further tightening said strip and adapted to be supported in yet another of said pairs of axially-aligned openings.

'7. For use with a dermatome of the type comprising a body member having a pair of spacedapart side walls having pairs of axially-aligned openings therein and joined by a bottom wall having an outer convex surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said outer convex surface; said attachment comprising first means for holding one end of said graft-transfer strip and adapted to be supported in one of said pairs of axiallyaligned openings, and second means for holding the other end of said graft-transfer strip with the intermediate portion of said strip against said outer convex surface, said second means "comprising a shaft adapted to be rotatably supported in another of said pairs of axially-aligned openings, means for securing said other end of. the grafttransfer strip thereto, and means for applying rotary motion to said shaft to draw said strip taut against said outer convex surface.

8. Structure as specified in claim 7, including means for retaining said shaft in rotated position with said graft-transfer strip drawn taut thereby.

9. An attachment for use with a dermatome of the type comprising a hollow body member having an outer convex surface against which a flexible graft-transfer strip is adapted to be temporarily retained taut; said attachment comprising a body portion adapted to be positioned within the hollow body member of the dermatome, first means for securing one end of a grafttransfer strip to said body portion, second means for securing the other end of said graft-transfer strip to said body portion with the intermediate portion of said strip overlying the dermatome outer convex surface, and means for drawing said strip taut.

10. An attachment for use with a dermatome of the type comprising a hollow body member having an outer convex surface against which a flexible graft-transfer strip is to be temporarily retained taut; said attachment comprising a body portion adapted to be positioned within the dermatome hollow body, first means carried by said body portion for securing to the latter one end of a flexible graft-transfer strip, second means carried by the body portion for securing the other end of said graft-transfer strip thereto with the intermediate portion of said strip positioned against the dermatome outer convex surface, and means for drawing said strip taut.

11. An attachment for use with a dermatome of the type comprising a hollow body member having an outer convex surface against which a flexible graft-transfer strip is to be temporarily retained taut; said attachment comprising a body portion adapted for reception within the derma- 7 tome hollow body, first securing means carried by said body portion for securing to the latter one end of a flexible graft-transfer strip, a supporting member pivotally mounted on said body portion, second securing means carried by said supporting member for securing to the latter the other end of said graft-transfer strip with the intermediate portion of said strip positioned against the dermatome convex surface, and means for adjusting said supporting member about its pivotal axis to draw said flexible grafttransfer strip taut.

12. For use with a dermatome of the type comprising a hollow body member having an outer convex surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said dermatome outer convex surface; said attachment comprising means for joining the two ends of a flexible graft-transfer strip, and means adapted to be positioned within said dermatome hollow body for taking up the slack in said strip after the ends thereof have been joined by said first-mentioned means, whereby the intermediate portion of said strip may be retained taut against the outer convex surface of the dermatome hollow body.

13. For use with a dermatome of the type comprising a hollow body having an outer convex surface, an attachment for temporarily retaining a flexible raft-transfer strip taut against said outer convex surface; said attachment comprising a member adapted to connect the two ends of a flexible graft-transfer member within said dermatome hollow body, and means adapted to be positioned within said hollow body for adjustably tensioning said flexible strip after connection of the ends thereof by said member, whereby the intermediate portion of said strip may be drawn taut against the outer convex surface of the dermatome hollow body.

14. For use with a dermatome of the type comprising a hollow body having a convex outer surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said convex outer surface; said attachment comprising a pair of spaced securing members adapted to grip opposit ends of the flexible graft-transfer strip within the hollow body of the dermatome, with the intermediate portion of said strip against the dermatome convex surface, and means for moving one of said securing means towards the other of said securing means, to draw the grafttransfer strip taut.

15. For use with a dermatome of the type comprising a hollow body having a convex outer surface, an attachment for temporarily retaining a flexible graft-transfer strip taut against said convex outer surface; said attachment including a frame adapted to be positioned within th hollow body of the dermatome, a first securing means for securing one end of the graft-transfer strip to the corresponding end of the frame, a supporting member mounted on the frame adjacent the other end thereof for movement relative thereto, a second securing means for securing the other end of the strip to said supporting member, and means for moving said supporting member relative to the frame to draw the graft-transfer strip taut against the dermatome convex outer surface.

16. An attachment for use with a dermatome of the type comprising a body member having an outer convex surface against which a flexible graft-transfer strip is to be temporarily retained taut; said attachment comprising a pair of holding means adapted to hold opposite ends of a flexible graft-transfer strip with the intermediate portion of said strip against the dermatome outer convex surface, and means supporting said pair of holding means relative to said dermatome body member, one holding means of said pair of holding means being adjustable relative to said supporting means and to said dermatome body member for drawing said graft-transfer strip taut against said dermatome convex surface,

17. Structure as specified in claim 16, wherein said supporting means comprises a pair of plates having portions projecting therefrom for interfltting with mating portions of the dermatome body member.

13. An attachment as specified in claim 16, wherein said supporting means comprises a pair of plates adapted to abut the sides of the dermatome body member, said plates having bosses projecting therefrom and adapted to be closely received in mating openings in the sides of the dermatome body member.

19. An attachment as specified in claim 16, wherein said supporting means comprises a pair of plates adapted to abut the sides of the dermatom body member, said plates having hook-like portions adapted to engage edges of the dermatome body member sides to position said plates with respect to said sides.

JOHN D. REESE.

REFERENCES CITED UNITED STATES PATENTS Name Date Reese Dec, 26, 1944 Number 

